Lipaugus pihas are large, dull colored passerines. Screaming Piha is a typical member of the genus; it is visually unobtrusive, but its piercing, distinctive call sets it apart. Both sexes are thrush like in appearance, but with a longer tail, shorter tarsi, and a broader bill than a thrush. Screaming Pihas are uniformly gray, although they are slightly paler on the belly and duskier on the tail.
Screaming Piha is broadly sympatric with Grayish Mourner (Rhytipterna simplex), and these two species frequently are syntopic. Both are gray, long tailed birds and so superficially are very similar. They are best distinguised by voice. The mourner also is significantly smaller than the piha, has a smaller, thinner bill, is more uniformly gray, and has reddish brown (not gray or gray brown) irides. The mourner also frequently associates with mixed species flocks, whereas the piha rarely if ever joins flocks.
Dusky Piha (Lipaugus fuscocinereus) also resembles Screaming Piha, but is much larger and is restricted to montane forests of the Andes; Dusky and Screaming pihas rarely if ever overlap geographically.
Adult: Sexes similar. The following description is based on Kirwan and Green (2011): Generally gray; remiges, greater wing coverts, and rectrices browner or duskier. Underparts are paler than the upperparts, and are palest on the throat.
Juvenile: Similar to the adult, but has cinnamon rufous wing coverts and tips to rectrices (Schulenberg et al. 2010).
Little information. Molt is seasonal in northern South America (Venezuela, Suriname, and Guyana; males initiate molt from February-May), and in eastern Brazil (where males initiate molt September-December), but there is little seasonality in the center of the range of the species (Snow 1982).
Iris: brown, gray, grayish brown
Bill: black, or maxilla black, mandible dusky with a pinkish dusky base
Tarsi and toes: black, dark olive, gray green, dark brown, dark gray
Bare parts color descriptions from Haverschmidt (1968), Snow (1982), Willard et al. (1991), and from specimens in The Field Museum.
Total length: 24–26 cm (Schulenberg et al. 2010), 24.5-25.5 cm (Ridgely and Greenfield 2009), 25 cm (Hilty 2003)
Linear measurements (from Snow 1982):
male (n = 10; Belém, Brazil):
wing length, mean 120.6 mm (range 118-123 mm)
tail length, mean 106.0 mm (range 101-110 mm)
tarsus length, mean 21.8 mm (range 20.5-22 mm)
culmen length, mean 15.6 mm (range 14.5-16.5 mm)
female (n = 10; Belém, Brazil):
wing length, mean 116.6 mm (range 112-123 mm)
tail lenth, mean 102.6 mm (range 95-105 mm)
tarsus length, mean 21.8 mm (range 21-22.5 mm)
culmen length, mean 15.9 mm (range 14.5-17 mm)
Mass: male (n = 5, Suriname), mean 72.6 g (range 71-74 g); male (n = 7, Peru), mean 81.9 g (range 77-85 g); male (n =2, Bolivia), 80 g, 83.4 g
female (n = 5, Surimane), mean 71.8 g (68-74 g); female (n = 5, Peru), mean 82.6 (range 78-87 g)
Mass data from Snow (1982).